Baseball bats, racquets, paddles and clubs are all commonly used in various sports where the object is to strike a moving or stationary ball in order to propel it some distance. These devices have certain problems in common as well as common objectives. A primary problem is the generation of a shock as a result of the impact of the ball with the bat, or racquet, or club, etc.
In a baseball bat the shock generated is most severe when the ball impacts a point other than the optimum striking point or "sweet spot" on the bat. The "sweet spot" is the point where the most impact energy will be delivered to the ball and the bat rebounds straight back and opposite to the ball's line of flight, and without any torquing, end for end, as rotation is developed. When this point is missed, some of the impact energy is delivered to the bat, off center, causing the bat to rotate, end for end, which results in both uncomfortable and injurious levels of shock being transmitted through the bat handle to the athlete. At best, this painful shock can rob the athlete of confidence and at worst, it can cause serious injury.
A significant advance in shock resistant baseball bats was disclosed in U.S. Pat. No. 5,180,163 issued to the present inventor Jan. 19, 1993. In this patent a baseball bat was disclosed having significant shock dampening capabilities including a tube member secured within the handle of the bat and having a spine member surrounded by a fluid. Such bat is highly efficient at dampening shock without adversely affecting the ball propulsion function of the bat.
Other baseball bats have been proposed and implemented which have attempted to dampen such shock and their consequences, albeit, all with significant limitations. Such limitations are undoubtedly a reason these bats have not received widespread acceptance.
For example, one such bat is disclosed in U.S. Pat. No. 4,951,948 issued to Peng where a cylindrical handle and main body are connected together and held by a retaining collar and an elastic ring. An elastic connector is provided axially attached to an end piece. Such shock absorbing bat did not provide for any relief from end torsional shock which is a primary factor for discomfort and injury, nor did such bat provide relief from the backwards reaction shock without diminution of the forward striking force which is directly and principally involved in propelling the ball.
Another genre of bat is disclosed in U.S. Pat. No. 4,898,386 issued to Anderson, where a training bat consisted of a hollow cylindrical bat having a disk positioned in the interior of the bat near its center. A plate was also positioned in the interior of the bat and an object was slideably positioned in the interior of the bat and was moveable between the disk and the plate. A hollow chamber having a knob is positioned at the handle end of the bat. Such bat had limited applications as a training device but was not useful in actual sport, nor did it provide adequate shock dampening functions.
Still another type of bat is disclosed in U.S. Pat. No. 3,955,816 issued to Bratt, where a warm-up bat having a hollow chamber with granular weight material distibuted therein to result in a practice ball bat with a distributed weight or bat-like feel. The handle section of such bat telescoped into one end of the tubular section filled with an aggregate of flowable material, such as sand. Such bat was not useable in actual sport as it had a deadening effect on the ball, and provided little, if any relief from the shock component responsible for discomfort and injury.
It would be highly desirable therefore to provide a means and method to specifically reduce the destructive shock generated by a bat after striking a ball while leaving the ball propulsion function of the bat essentially unchanged.